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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

27329 results found.

  1. LIGO/Virgo S191204r: no counterpart candidates in the Swift/BAT observations
  2. GRB 191205A: Fermi GBM Final Real-time Localization
  3. IceCube-191204A: Upper limits from Fermi-GBM Observations
  4. IceCube Alert 191204.95: Global MASTER-Net observations report
  5. LIGO/Virgo S191204r: not observable by Fermi-GBM
  6. LIGO/Virgo S191204r: Coverage and upper limits from MAXI/GSC observations
  7. LIGO/Virgo S191204r: Global MASTER-Net observations report
  8. GRB 191202A: Fermi-LAT detection
  9. GRB 191202A: Fermi GBM observation
  10. Fermi trigger No 597049044: Global MASTER-Net observations report
  11. GRB 191203A: Fermi GBM Final Real-time Localization
  12. GRB 191202A: Fermi GBM Final Real-time Localization
  13. LIGO/Virgo S191129u: No transient candidates in CALET observations
  14. Fermi trigger No 596786686: Global MASTER-Net observations report
  15. Fermi trigger No 596808579: Global MASTER-Net observations report
  16. Fermi GBM trigger 596808579/191130507 is not a GRB
  17. LIGO/Virgo S191129u: Upper limits from Insight-HXMT/HE observations
  18. LIGO/Virgo S191129u: No counterpart candidates in Fermi-LAT observations
  19. LIGO/Virgo S191129u: not observable by Fermi-GBM
  20. LIGO/Virgo S191129u: Swift/BAT in SAA
  21. LIGO/Virgo S191129u: No counterpart candidates in HAWC observations
  22. LIGO/Virgo S191129u: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S191129u: Global MASTER-Net observations report
  24. Fermi trigger No 596690552: Global MASTER-Net observations report
  25. GRB 191129A: Fermi GBM Final Real-time Localization
  26. Baksan Neutrino Observatory Alert 191128.17: Global MASTER-Net observations report
  27. GRB 191125B: MASTER-VWFC synchronous observation
  28. Baksan Neutrino Observatory Alert 191127.25: Global MASTER-Net observations report
  29. Fermi trigger No 596387570: Global MASTER-Net observations report
  30. GRB 191125B: Fermi GBM Final Real-time Localization
  31. GRB 191125A: Fermi GBM Final Real-time Localization
  32. Baksan Neutrino Observatory Alert 191124.13: Global MASTER-Net observations report
  33. LIGO/Virgo S191124be: Global MASTER-Net observations report
  34. LIGO/Virgo S191124be: Retraction of GW compact binary merger candidate
  35. GRB 191123A: Swift/UVOT further analysis
  36. GRB 191123A: Swift-BAT refined analysis
  37. GRB 191123A: Swift-XRT refined Analysis
  38. GRB 191123A: iTelescope optical upper limits
  39. GRB 191123A: Swift/UVOT detection
  40. IceCube-191122A: Global MASTER-Net observations report
  41. GRB 191123A: Swift detection of a burst with an optical counterpart
  42. GRB 191118A: Insight-HXMT/HE detection
  43. GRB 191122A: Swift/UVOT Upper Limits
  44. GRB 191122A: Swift-BAT refined analysis
  45. GRB 191122A: Swift-XRT refined Analysis
  46. GRB 191122A: BOOTES-4/MET optical limit
  47. GRB 191122A: Swift detection of a burst
  48. LIGO/Virgo S191120at: Retraction of GW compact binary merger candidate
  49. LIGO/Virgo S191120aj: Global MASTER-Net observations report
  50. LIGO/Virgo S191120aj: Retraction of GW compact binary merger candidate
  51. IceCube-191119A: Upper limits from Fermi-GBM Observations
  52. GRB 191118A: BALROG localization (Fermi Trigger 595807926 / GRB 191118925)
  53. GRB 191118A: Fermi GBM Final Real-time Localization
  54. GRB 191117B: Fermi GBM Final Real-time Localization
  55. LIGO/Virgo S191117j: Retraction of GW compact binary merger candidate
  56. GRB 191117A: Fermi GBM Final Real-time Localization
  57. Swift Trigger 937114 is not an astrophysical source
  58. Swift GRB191115A: Global MASTER-Net observations report
  59. LIGO/Virgo S191110af: Retraction of GW unmodeled transient candidate
  60. LIGO/Virgo S191110af: Upper limits from KM3NeT MeV neutrino search.
  61. GRB 191111A: Insight-HXMT/HE detection
  62. GRB 191027A: CALET Gamma-Ray Burst Monitor detection
  63. GRB 191113A: Fermi GBM Final Real-time Localization
  64. GRB 191031D: CALET Gamma-Ray Burst Monitor detection
  65. GRB 191112A: Fermi GBM Final Real-time Localization
  66. LIGO/Virgo S191110af: Swift XRT observations, no secure afterglow found
  67. LIGO/Virgo S191110af: Upper limits from CALET observations.
  68. LIGO/Virgo S191109d: Not observable by CALET
  69. LIGO/Virgo S191110af: no counterpart candidates in the Swift/BAT observations
  70. GRB 191111B: BALROG localization (Fermi Trigger 595170435 / GRB 191111547)
  71. GRB 191111B: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo S191110af: No neutrino counterpart candidate in ANTARES search
  73. LIGO/Virgo S191110af: No counterpart candidates in Fermi-LAT observations
  74. GRB 191111A: Fermi GBM Final Real-time Localization
  75. LIGO/Virgo S191110af: Upper limits from Fermi-GBM Observations
  76. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  77. LIGO/Virgo S191110af: Global MASTER-Net observations report
  78. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  79. LIGO/Virgo S191110x: Retraction of GW compact binary merger candidate
  80. LIGO/Virgo S191110x: Global MASTER-Net observations report
  81. LIGO/Virgo S191109d: No counterpart candidates in Fermi-LAT observations
  82. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  83. GRB 191110A: Fermi GBM Final Real-time Localization
  84. LIGO/Virgo S191105e: Upper limits from Insight-HXMT/HE observations
  85. LIGO/Virgo S191109d: AstroSat CZTI upper limits
  86. LIGO/Virgo S191109d: no counterpart candidates in the Swift/BAT observations
  87. LIGO/Virgo S191109d: Global MASTER-Net observations report
  88. LIGO/Virgo S191109d: Upper limits from Fermi-GBM Observations
  89. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  90. GRB 191108A: Fermi GBM Final Real-time Localization
  91. GRB 191106A: Swift/UVOT Upper Limits
  92. GRB 191106A: Swift-BAT refined analysis
  93. LIGO/Virgo S191105e: AstroSat CZTI upper limits
  94. LIGO/Virgo S191105e: Not observable by CALET
  95. LIGO/Virgo S191105e: No counterpart candidates in Fermi-LAT observations
  96. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  97. LIGO/Virgo S191105e: no counterpart candidates in the Swift/BAT observations
  98. GRB 191106A: NOT optical upper limit
  99. GRB 191106A: Swift-XRT refined Analysis
  100. LIGO/Virgo S191105e: No counterpart candidates in HAWC observations

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